Hoisting mechanism



` April 5, 193s,

C. G. EISENBERG, JR

HOISTING MECHANISM s sheets-'sheet 1 Filed April 28, 1957 ,r

April 5, 1938. K

C. G. EISENBERG, JR

` HolsTING MEoHANIsM Fild April 28, `193'? 3 Sheets-Sheet 2 ATToRNEYApril 5, 1938.

C. EISENBERG, JR

HOISTING MECHANI SM Filed April 2.8, 1957 3 Sheets-Sheet 3v I lNvENT-uBY l I f ATTORN@ 'Patented pr. 5, 1938 UNITED STATES ZHBGM PATENT orticanorsmo. MECHANISM poration of Wisconsin Application April 2s, 1937;serial No. 4139,476

` 4 Claims.

My 'present invention relates generally to improvements in the art ofcontrollably lifting and' lowering relatively bulky and heavy objects,and relates more specifically to improvements in the 5 construction andoperation of fluid pressure actu- Y ated hoisting mechanism foreffecting dumping of the load carrying body of a dump truck or the like.

Generally dened, an object of the present iuventicn is to provideimproved uid pressure actuated hoisting mechanism for tiltable loadcarrying bodies or the like, which is simple, compact l and durable inconstruction, and which is moreover highly efdcient in operation. Y Itis common commercial practice in the art of transporting materials inbulk with the aid oi motor trucks, to utilize tiltable load carryingbodies which are adapted to be dumped by means of hydraulic hoists.- Thedump body is ordinarily pivotally attached at its rear end to therear'of the truck chassis, and the hoists of which there may be one ormore, 'usually have their cylinders pivotally suspended from the chassisbeneath the front of the body and are provided with piston rodspivotally attached directly to the bottom of the body forwardly of therear body suspension pivot. In large capacity 'dump trucks, the bodiesare frequently of relatively great size and extend considerabledistances laterally beyond each side of the chassis, and it then becomesdesirable to provide two simultaneously operable hoists 1ocated one oneach outer side of the truck chassis in front of the rear drivingwheels. Due to the fact that these hoists are often required to liftextremely heavy loads, the cooperating hoists which'deliver the liftingforce against the bodies at varying angles, must be rigidly supported soas to prevent relative displacement or misalinement of the severalhoists due to unequal load 40 distribution on the bodyor possibleweaving or other distortion of the truck chassis. The hoist supportsmust also-avoid interfering with the truck driving mechanism; and sinceit is preferable to utilize a hoist actuating pump which is' preferablylocated near the hoists and 'driven from the truck propelling motor, thehoist sus'- pension structure must also be as compactas' possible so asto make room for the pump andthe liquid supply reservoir. All of theserequirements tend to introduce many difcult problems in the constructionof such vdual outside mounted hydraulic hoisting systems.

It is therefore a more specific object of my present invention toprovide an improved fluid pressure actuated hoist system embodyingoutnism for delivering actuating uid to and from 35 I the hoistcylinders at all times, without danger4 of leakage.

Still another specic object of the invention is to provide an improvedmounting for a plurality of simultaneously operable hydraulic hoists, 20wherein the cylinders 'of the hoists are overhung with respect to acentral support and are subjected to variable forces tending Ato throwthe same out of true alinement during normal operation.

An additional specific object of my invention is to provide a new. anduseful twin hoist assemblage which is adapted to be mounted as a unitupon the chassis of a truck, so that the hoists .and the supportstherefor will cause minimum '50 obstruction and interference with thedriving and other mechanisms forming part of the truck as-` semblage. g

vThese and other specific objects and advantages will be apparentfromthe following detailed 35 description.

A clear conception of embodiments of the several features constitutingthe present invention,` and of the mode of constructing and of operatinghoisting mechanisms built in accordance with 40 y the improvement, maybe had by referring to the drawings accompanying and forming a part ofthis specification wherein like reference charactersdesignate the sameor similar parts in the variousviews. y

Fig. 1 Vis a somewhat diagrammatic side view of the rear portion of adump truck showing the body in normal position in solid lines, and inextreme tilted position in'dot-and-dash lines: 50I

Fig. 2 is a top view of the assemblage of Fig. 1,

- showing the outline of the dump bodyin dot-anddash lines; y v

Fig. 3 is an enlarged fragmentary side view of the upper portion of oneof the hoists and of the 55 pump for delivering huid thereto, `thecontrol y valve for the pump being shown insection;

Fig. 4 is a similarly enlarged section through the pump control valve ofFig. 3, showing the valve in hoist lowering position;

Fig. 5 is a part sectional top view of the as- 'semblage of Fig. 3,showing one of the hoists and taken along the line 6-3 oiFig. 5;

Fis. 7 isa fragmentary transverse vertical seiction through one side ofthe chassis and dump body, showing a lfront view of fragments of one ofthe hoists and of thel pump;

f Fig 8 is a central vertical section of one type of hjo'ist such as maybe utilized in my present improved system;

`Fig. 9 is a transverse vertical section through the hoistsupportingbeam, the section being taken through one of the pumpsupports; and

Fig. 10 is a front view of a modiiied type of connection for conductinguid to and from one of the hoists through the trunnion thereof. While Ihave illustrated my invention herein as being specifically embodied in atwin telescopic hydraulic hoisting system for an end dump bodyassociated with a motor driven truck, itis not my intention to therebyunnecessarily restrict the scope, since some of the features areobviously -more generally applicable to other types of iluid pressureactuated hoisting systems utilizing other kinds of hoist assemblages.

Referring to the drawings, and more especially tothe typical assemblageof Figs. 1 and `2, the improved hoist and body system comprises ingeneral a vehicle chassis' I4 mounted upon rear propelling wheels I5; adump body It tiltably mounted upon the rear portion of the. chassis Ilby means of a transverse pivot I1 and extending forwardly over thechassis and laterally beyond the opposite sides thereof; and a hydraulichoist assembly consisting of a- U-shaped frame including transverse boxbeam I8, hoisting cylinders Il pivotally suspended from the op .pistons20 movable wi the cylinders I3 and being operatively associated with thebody I3,and a pump 2| operable by the vehicle propelling motor forsupplying fluid such as oil under pressure to the hoist cylinders I3from a supply reservoir 22.

The vehicle chassis I4 is ordinarily formed of elongated parallel sidebeams which are suitably braced and interconnected by transverse braces.

" Figs. 1 and 2, and the bottom of the body I3 is reenforced bylongitudinal I-beams 23 to which the pistons 20 are attached by means ofpivot pins 24. Y

The improved hoisting unit or assembly which is shown dia-grammaticallyinFigs.A 1 and 2, is illustrated more in detailin Figs. 3 to 9inclusive. The single box beam I 8 which constitutes the sole supportfor the hoist imit, has rectangularly polygonal cross-section' as shownin Fig. 9,

te ends of the beam I3,

anso

being formed of heavy sheet metal plates welded jections 26 firmlysecured to the beam I3 by welding or otherwise, and extending outwardlybeyond the opposite sides of the chassis Il; and a set of parallelbearing bars `21, 23 is rigidly attached to and extends forwardly awayfrom each of these rigid end projections -26 beyond each side of thechassis. 'Ihe front ends of the bearing bars 21, 23 of each set, arermly interconnected by means of braces29; and the tops of the inner bars21' and the adjacent ends of theb'races 29 are additionally strengthenedand connected to the top plate of the box beam I3y by means ofreenforcing plates 3B as clearly shown in Fig. 5. The transverse beam 23and the inner bars 21 obviously provide a rigid-horizontally disposedU-shaped frame which rests directly upon the chassis I4, and theprojections 26Kextend outwardly beyond this frame. The outer bearingbars 23 are detachably secured to the outer ends of the projections 26"and of the braces 29 by nuts -3I as illustrated in Figs. 3 and 5; andthe medial Portions of the bars 21, 28 o'f each set, areprovided withaligned bearings 32 for swingably supporting the hoists. The inner bars21 are also provided with depending plates 33 as shown in Figs. 'I and8,- which coact with the opposite sides of the adjacent chassis sidebeams in order to properly position the hoist supporting structure.

Each of the hoist cylinders I9 is provided with an integral hollow innertrunnion 34 and with anintegral solid outer trunnion 35, these trunnions34, -35 being aligned and located near the upper ends of the cylinders I9, and also being journaled in the bearings 32 so as to permit thecylinders to swing in order to accommodate the -varying angularity ofthe axes of the pistons 20 during lifting and lowering of the bod'y I3.lThe inner hollow trunnion 35 of each cylinder I3 is provided with athrough passage, the end of which communicates with and provides asupport for a iluid supply valve casing 36, and the opposite end ofwhich is in open communication -with a diict 31 formed in the cylinderwall and leading into the lowe'r end of cylinder I3 as illustrated inFigs. 7 and 8. The pistons 2II of which there may be one or morein eachcylinder, depending upon the lift required, are slidable upwardly withinthe cylinders I3 by liquid under pressure admitted -through the ducts31, and are movable downwardly to discharge theliquid from within thecylinders Il through these ducts, by gravity acting upon the body I6andpistons 2II. It is to be understood that the type of hoist -used mayvary in accordance with the requirements, and that either asinglefpiston or any desired. number of telescopic pistons 20- may beutilized.

Each valve casing 3 6 has therein a spring pressed ballcheck valve 3lfor permitting delivery of liquid under pressure to the correspondingcylinder port 31 while preventing escape of the fluid past this valve,and a second valvel casing -33 is attached to each casing 33 by means ofcap screws Il as shown in Figs. 3, 5 and 7. The casings 33 are providedwith ports II leading tothe attacca spending valves 38, d3, are-in opencommunication with one end of a exible hose connection t6, and thesehose connections QS extend through enlarged slots or openings in thebeam lil and have their opposite ends xedly attached to the pump 2i incommunication withliquid distributv ing port lll. The port il connectsdirectly with the pump discharge conduit il@ and'has a oy-pass duct G9leading to a control valve 5t as shown in Figs. 3 and a;v and thesuction conduit 5l of the pump 2l also communicates with the valve tit.The conduit E2 which` communicates with the valve 5B between the ductil@ and the'conduit 5i, leads to the liquid supply reservoir 22, and thevalve 5i) is or the rotary balanced type.

The control valve i5@ has a depending actuating lever 5S which issimilar to the lever d5 for the by-pass valves 43, and the lowerswinging ends of both of the levers 35, 53 are joined by a connection5G. The lever l5 is additionally provided withan actuating vconnection55 which extends forwardly to an accessible actuating station, andthearrangement is obviously such that the valves d3, 5B aresimultaneously manually operable to either deliver liquid under pressureto both cylinders l, or to permit free exhaust of the actuating iluid tothe reservoir 22. The pump 2i is oi the well known gear type, and thedriving shaft 5t ofthis pump is adapted to be driven from the vehiclepropelling motor through countershaits 5l, 5S and universal joints 552.in a well known manner. It is to be noted, that by mounting both hoistsand the pump 2l directly upon the beam structure; these elements arealways maintained in proper alignment regardless' of possible distortionof the chassis it, and this common mounting also permits most conveniient assemblage of the entire hoisting system.

`While the use of the valves i3 is desirable in order to prevent thebody it from lowering accidentally due to breakage of the hoseconnections 13S or otherwise, these valves may be dispensed with, and anassemblage such as shown in Fig. l0 may be utilized. In this modifiedconstruction, the valve asings 36 are replaced by conduit nttings i533which are permanently secured to the inner trunnions 34 and communicatewith the cylinder ducts 37. The other -valve casings 39 are replaced byelbow ttings tl xedly attached to pipes passing through the beam it andcommunicating with th'e port il in the pump casing, so that the port diis 'in constant open communication with the cylinder ducts 3l'. Theelbow fittings 6l have spherical sockets with which sphericalprojections 52 formed on the fittings Sil, coact, and the `fittings Si);Si of each set are connected by a coupling collar $3 which permitsswinging or angular displacement of the alined fittings til with thecylinders i@ relative to the fittings tl without danger of leakage.

During normal operation of the improved hoisting mechanism, and assumingthe same to have been properly assembled and applied to the vehiclechassis lf3, the overhanging hoists at the opposite side of the chassisi@ are simultaneously operable at the will of the operator, to raise thebody i6 from the position shown in full lines in Fig. 1, to the positionshown in dotand-dash lines, and to lower the same. The pump 2l may beplaced in operation by drivingly connecting the same to the vehiclepropelling motor, and when the control valves t3, t0 are positioned asshown in Figs. 3, 5 and 6, the pump 2l is withdrawing liquid from thesupply reservoir 22 through the conduit 52, past the valve iii) andthrough the suction conduit 5i, and is delivering the liquid underpressure through the conduit 43, ports ill, hose connections d6, portsdi, and pastvthe ball valves 38 into the cylinders le. The fluid underpressure thus admitted to the cylinders I9, causes the pistons 2ttherein to move upwardly and to thereby tilt the body i6. 'When the bodyi6 has been tilted to'its eX- treme position, the. pump 2i will functionto bypass the excess liquid in a well'known manner, and the nonreturnvalves Swill prevent escape of :duid from within the cylinders l@through the ducts 3l. When it is desired to lowerthe bodyl it, it isonly necessary for the operator to manipulate the connections 55, 54 soas to throw the valves di, 5@ to the opposite extreme position, thevalve 5@ being shown in such position in Fig. 4. When the valves arethus adjusted, the passages l are connected with the ports di, therebyestablishing free communication between the interiors of the cylindersit and the hose connections 3b. The ports di are also connected to theconduit 52 through the ports i9 and the valve till, thereby permittingfree escape of liquid from the cylinders it to the reservoir 222. Theweight oi the body it and of the pistons til will then cause the formerto lower until the beams 23 coact with. the cross beam it whichconstitutes thesupport for the hoists. In this manner, the body it maybe raised or lowered at will, and may bel retained in elevated of thevalves d3.

Ii an assemblage such as shown in Fig. 10 is used, the control ofadmission andl discharge of iiuid to and from the cylinders itiseffected solely by manipulation of the valve 5t. In either case, thecylinders i9 VVA `are free to swing about their trunnions 313, 35 s o asto accommodate the displacement thereof. during swinging of the body itabout its pivot il. The hose connections it will obviously accommodatesuoli. relative motion of parts, and the same is true of the swingconnection shown in Fig. l0.

yThe specific formation of the hoist supports is en .importa-nt featureof the present invention. Due to the relative great overall width of thebody ifi, the cylinders i9 are preferably located on opposite sides of vof the fact that .the hoists exert a tremendous pressure against thebody i5` during elevation of the latter. the cylinders i9 must bermly'rnounted. The beam i8 is therefore formed with a rectangular boxsection and has a relatively wide loweriace which directly engages theside beams of the chassis it. The end projections 25 are rigidlyattached to the beam i8 by welding, and the side bars 28, ''llar'e nrmlysecured. to the projections 26 and have their forward ends rigidlyinterconnected by the members 29. The top plates 3d additionallyreenforce andl stiffen the position by proper setting assemblage and thedepending plates 33 secured ders i9 are provided with upper trunnions34, 35

the chassis i6, but because which are journaled directly inthe bearings32 carried by the bars 21, 28, and by providing upper trunnions-for thecylinders Il, bbstruction to the driving mechanism of the vehicle isetl'ectively prevented. The mounting of-the pump 2l di- Y rectly uponthe hoist supporting beam It, is also desirable since possiblemisalignment of parts is thereby avoided, and the entire assemblage canmoreover be handled as a unit and applied vto standard chassis frames.

V- From the foregoing detailed description, it will support-the hoistingcylinders so as to meet even thel severest requirements. While theimproved twin hoist assemblage is especially adapted for cooperationwith-a dump body which is tiltably suspended from a vehicle chassis,this assemblage may alsobe utilized for other purposes, and the hoistmounting permits the assemblage to be` quickly and eilectively appliedto any support such as a vehicle chassis. The improved distribution andcontrol mechanism for delivering actuating fluid to and from the hoistcylinders,

is not subject to leakage, and by utilizingthe valves associateddirectly with the inner trunnions, the body I6 cannot drop in case thehose connections shouldbreak. The improved hoist mounting, whileproviding a' iirm support for maintaining the hoists in alignment, doesnot interfere with the driving mechanism for the rear wheels, or-withany other structure forming'a part of the vehicle, and this hoistsupport also provides a suitable stop for the body Ii when the .latteris in lowered position. 'I'he hoist supporting beam also provides aconvenient Support for the pump, and the supporting assemblage may bereadily constructed -from heavy sheet metal rigidly interconnected bywelding. The removable nuts associated with the end projections of v thebox beam and with the cross members 29, also facilitate assembly` of theunit and removal of the hoists in case this becomes desirable.

It should be understood that itis not desired to limit the presentinvention to the exact details of construction or to the precise mode ofoperation, herein shown and described, for various modifications within'the scope of the claims may occur to persons skilled in the art.

I claimz- A1. In combination, a vehicle chassis having opposite sidebeams, a dump body carried by said chassis, a ULshaped frame comprising'a single with said body.

transverse beam extending across and projecting outwardly beyond saidchassis and `laterally spaced inner bearing bars rigidly associated withsaid transverse beam and resting directly upon said chassis beams, outerbearingbars secured to theouter ends of said transverse beam and beingspaced from said inner bars, and a hoist pivotally suspended betweeneach set of said outer and inner bars directly adjacent to thecorresponding chassis beam, said hoists being operatively associatedwith said body.

2. In combination, a vehicle chassis having op posite sides, a dump bodysuspended from said chassis, a horizontal U-shaped frame comprising asingle transverse beam crossing and projecting outwardly beyond saidchassis and laterally spaced inner bearing bars rigidly secured to saidtransverse beam and resting directly upon said chassis beams, outerbearing bars secured to the outer ends of said transverse beam .andbeing spaced from said inner bars, means rigidly connecting'the ends ofeach set of inner and outer bars remote from said transverse beam, and ahoist pivotally suspended between each set of said outer and linner barsdirectly adjacent to the corresponding chassis beam, said hoists beingoperatively associated with said body to move the same.

relative to said chassis.

3. In combination, a vehicle chassis having opposite parallel sidebeams, a dump body pivotally suspended from said chassis beams, ahorizontal U-shaped rigid frame comprising a single transverse box beamresting upon and projecting outwardly beyond said chassis'and laterallyspaced inner bearing bars rigidly associated with said box beam andresting directly upon said chassis beams, outer bearing bars secured tothe outer extremities of said transverse beam and being spaced from saidinner bars, and a holst pivotallysuspended at its upper end betweeneachset of said outer and inner bars directly adjacent the correspondingchassis beam, said hoists being loperatively associated withv said bodyt'o swing the same.

4. In combination, a vehicle chassis, a dump ,body carried by saidchassis, a U-shaped rigid frame having inner side bars resting directly-upon said chassis and a single cross-beam rigidly interconnecting thecorresponding ends of said side bars and projecting outwardly beyond thechassis,

outer bearing lbars secured to the outer ends of Said cross-beam andbeing spaced from said inner" bars, `and a hoist pivotally suspendedbetween each 4set of said outer and -inner bars directly adjacent thecorresponding outer side of said chassis, said hoists being operativelyassociated CHARLES G; ISENBERG, Jn,

